Zoroaster. The Key to the Art - Adam McLean; Zoroaster

This book, the Clavis Artis, presents itself as being a translation into German of an ancient Arabic work by an alchemical adept named Zoroaster. It uses a number of Arabic-sounding words for alchemical substances in the opening section of its thirteen chapters. It is instead a work of the Eighteenth Century and is closely related to the books of Abraham the Jew by Abraham Eleazar and that of Samuel Baruch's Donum Dei, both of which incorporate the same Arabic-sounding words for alchemical substances.

The text itself has remarkably detailed descriptions of alchemical processes and experiments.

There are a number of Eighteenth-Century manuscripts of the Clavis Artis in three volumes with many emblematic coloured drawings. This printed version seems to be a transcription of the first volume.